To detect that a date is yesterday using JavaScript:
Step 1. Get value of a day in milliseconds
Step 2. Get today's date using Date() object
Step 3. Subract today's date in milliseconds from day value
Step 4. Convert date string to be checked to date object within Date()
Step 5. Then convert date object into milliseconds
Step 6. Check if date to be checked is equal
Here are a couple of examples below:
function isYesterday (dte) {
const day = 1000 * 60 * 60 * 24; // get one day in millidsecods
let now = new Date(); //get today's date
let checkDate = new Date(dte); // convert date string to object
now = new Date(now.getTime() - day); //difference between a day and date being checked in milliseconds
if(checkDate.getDate() == now.getDate()){
return true;
}else{
return false;
}
}
console.log(isYesterday("2022-08-16")); //true
console.log(isYesterday("2022-08-12")); //false